# a = 10
# b = 20
def operation(a, b, operator):#形参，默认值
    # 计算机
    # 输入两个数a和b，计算a和b的操作：+、-、*、/、//、%、**、sin、cos、tan、cot
    a = float(input("请输入一个数a:"))
    b = float(input("请输入一个数b:"))
#def operation2(*para):
    #sum1 = 0
    #for item in para:
        #sum1 = sum1+item
        #print("多个数的和是:", sum1)


flag = 1
#list1=[]
while flag == 1:
    operator = input("请输入你要做的运算吧(+、-、*、/、//、%、**、sin、cos、tan、cot):")
    a = float(input("请输入一个数a:"))
    b = float(input("请输入一个数b:"))
if operator == "+":
    print("a" + operator + "b= ", operation(a, b, operator))
elif operator == "-":
    print("a" + "_" + "b= ", operation(a, b, operator))
    flag = int(input("继续(1)或退出(0)?"))
elif operator == "**":
    print("a" + "operator" + "b= ", operation(a, b, operator))  # 关键子参数
    flag = int(input("继续(1)或退出(0)?"))

c = int(input("请输入一个数c:"))
d = int(input("请输入一个数d:"))
print("c和d的和是:", c + d)